There has been hitherto known a medical probe for observing an object using pulse lights of a plurality of different wavelengths irradiated from a light source, the probe having: a light guide unit guiding the pulse light incident from the light source to emit the light to the object; and an optical delay unit for giving, with respect to reflected pulse light from the object irradiated with the emitted pulse light, a predetermined delay time that is different for each wavelength, the probe outputting the pulse light which is given the delay time to a predetermined photodetector (see, for example, Patent Literature 1). This configuration is considered to allow for reducing to one the number of the optical detectors.
Another conceivable technique that allows for reducing to one the number of optical detectors may involve sequentially switching lasers of red, green, blue along with a sampling rate as illustrated in FIGS. 10A-10C for example, so as to sequentially irradiate pulse light of each color onto the object.